qcacmn: Add MSDU length for the first RX fragment buffer

When fragment buffer received in REO2SW, MSDU length only valid
in the last fragment, need to copy that value to first fragment
for following process.

Change-Id: Ib3fbc07b11662fc161402befbb8396519fcebd33
CRs-Fixed: 3790059

dp/wifi3.0/dp_rx.c

@@ -1829,7 +1829,7 @@ static inline uint32_t dp_get_l3_hdr_pad_len(struct dp_soc *soc,
 
 qdf_nbuf_t dp_rx_sg_create(struct dp_soc *soc, qdf_nbuf_t nbuf)
 {
-	qdf_nbuf_t parent, frag_list, next = NULL;
+	qdf_nbuf_t parent, frag_list, frag_tail, next = NULL;
 	uint16_t frag_list_len = 0;
 	uint16_t mpdu_len;
 	bool last_nbuf;
@@ -1842,6 +1842,19 @@ qdf_nbuf_t dp_rx_sg_create(struct dp_soc *soc, qdf_nbuf_t nbuf)
 	 */
 	mpdu_len = QDF_NBUF_CB_RX_PKT_LEN(nbuf);
 
+	/*
+	 * If MSDU length of the first fragment is zero, need to
+	 * use the length of the last fragment to overwrite.
+	 */
+	if (!mpdu_len) {
+		frag_tail = nbuf;
+		while (frag_tail && qdf_nbuf_is_rx_chfrag_cont(frag_tail))
+			frag_tail = frag_tail->next;
+
+		if (frag_tail)
+			QDF_NBUF_CB_RX_PKT_LEN(nbuf) =
+			    QDF_NBUF_CB_RX_PKT_LEN(frag_tail);
+	}
 	/*
 	 * this is a case where the complete msdu fits in one single nbuf.
 	 * in this case HW sets both start and end bit and we only need to